One producer said there are continuing signs of tightness in the market, as demand from the oil and gas production sector remains strong in the southwestern US. HCl is used extensively in the hydraulic fracturing, or fracking, process in shale plays.

Another producer, however, said there has yet to be the level of tightness in the market based on the trend seen in 2011.

But as production of isocyanates, a co-product of HCl, begins to taper off toward the end of the year, the restriction in supply is likely to continue, the producer said.

Meanwhile, a distributor meanwhile said it has yet to see any restriction in supply and that there is plenty of material available.

Major US manufacturers of HCl include Occidental Chemicals, BASF, Olin, Bayer and Dow.